French prosecutors yesterday dropped gang-rape charges against Dominique Strauss-Kahn, after an alleged victim recanted her tale and said she had consensual sex with the international horndog.

The Belgian prostitute, who had a rendezvous with DSK in Washington, DC, in 2010, admitted she was not forced to have sex with the former International Monetary Fund chief, according to prosecutor Frédéric Fèvre in the French city of Lille.

The complaining witness in May said that accomplices pinned down her hands and feet while DSK allegedly sodomized her at the W Hotel in DC.

The woman has since sent a letter to prosecutors, claiming she was paid to have consensual sex and she didn’t want to assist the case against DSK, a one-time French presidential hopeful.

Strauss-Kahn’s defense has admitted that he has participated in sex parties in Washington but never forced himself on anyone. He also denies knowing that any of his orgy partners were pros.

DSK’s defense lawyer, Henri Leclerc, said yesterday of the accusations against his client, “The whole case is groundless.”

DSK, 63, had been a considered a favorite for the French presidency until he was arrested in Manhattan on May 15, 2011, after Nafissatou Diallo, a maid at the Sofitel hotel on West 44th Street, accused him of attempted rape.

The Manhattan DA dropped the criminal case after investigators caught Diallo in several lies, including the claim that she had been gang-raped in her native Guinea.

She has since filed a civil suit against DSK in The Bronx.

The Washington incident was investigated by prosecutors in Lille because it allegedly stemmed from a prostitution ring based out of the luxury Carlton hotel in the northern French city.

Strauss-Kahn could still face French charges for alleged pimping.

Prostitution itself is not illegal in France, but pimping is. So prosecutors would have to show that DSK played a role in organizing the sex parties and procuring the professional entertainment.

“As for the rest of the case . . . the presence of prostitutes at these evenings does not constitute a pimping offense,” said Leclerc.